Nirmal Sen (independence activist)

Nirmal Sen
Sen as a student at Chittagong Medical College.
Born	1900 Raozan Upazila,,Chittagong, Eastern Bengal and Assam, British India
Died	12th June, 1932, Patiya,Chittagong, Bengal, British India
Cause of death	gunshot wound
Other names	Nirmal Kumar Sen
Alma mater	Chittagong Medical College
Known for	Chittagong armoury raid
Parents	Rasik Sen (father) Harasundari devi (mother)

Nirmal Sen also known as Nirmal Kumar Sen (Bengali: নির্মল সেন) (1900 – 12th June 1932) was an Indian independence activist and a member of the armed resistance movement led by Surya Sen, which carried out the Chittagong armoury raid in 1930. Went to Burma in 1920 for securing arms and ammunition. Took part in the Non-Cooperation Movement (1921). Arrested in 1924 and detained without trial for 3 years. One of the ringleaders of the Chittagong revolutionary party and also provided funds for the Party. Participated in the Chittagong Armoury Raid on April 18, 1930, and in the fighting against British troops on the Jalalabad Hill on April 22, 1930. Escaped after the raid and remained in hiding. On June 13, 1932 he got surrounded by a British military squad in the house of Savitri Chakrabarty at Patiya Upazila on June 13, 1932. Shot dead a British officer Captain Cameron, in the encounter and was himself killed.

Early life

Nirmal Kumar Sen, a participant in the Chittagong Armoury Raid, was born in 1900 in the village of Koyepara in Raozan Upazila, Chittagong. His parents were Rasik Sen and Harasundari Devi. He was the youngest of five siblings—three sons and two daughters. His eldest brother, Jamini Ranjan Sen, was employed by the Assam Bengal Railway in Chittagong.

In 1905, Sen's family relocated to the Firingi Bazar area of Chittagong city. He attended Chittagong Government School, where he came under the influence of revolutionary ideologies, particularly through the mentorship of Nripendra Chandra Bandopadhyay. During this time, he was also a classmate of Surya Sen, who would later lead the Chittagong Armoury Raid.

Sen pursued higher education at Chittagong Medical College, where he became actively involved in the Indian revolutionary movement. He joined the Chittagong branch of the Anushilan Samiti, a prominent revolutionary organization active during British rule in India.

Due to his clandestine activities, Sen maintained minimal contact with his family. However, he occasionally visited his mother and his sister-in-law, Nalinibala Sen, who was reportedly supportive of his revolutionary involvement. According to accounts, she provided shelter and assistance to several revolutionaries during periods of police surveillance, helping to ensure their safety while they were in hiding.

Joining revolutionary party

Following the end of the First World War in 1918, Nirmal Sen was a student at Chittagong Medical College. During this period, a secret revolutionary organization began to take shape in Chittagong. The group’s central committee included Surya Sen, Ananta Singh, Anurup Sen, Nogen Sen (also known as Julu Sen), Ambika Chakrabarty, and Charubikash Dutta. Sen became one of the early and active members of this underground network.

In 1921, Mahatma Gandhi launched the Non-cooperation movement (1919–1922), advocating for nonviolent resistance against British colonial rule. Around this time, ideological divisions emerged within Surya Sen’s group. Disagreements over strategy and philosophy led to internal rifts; as a result, members such as Charubikash Dutta and Pramod Ranjan Choudhury shifted their allegiance to the Anushilan Samiti, while Surya Sen and his close associates maintained ties with the Jugantar group.

After the suspension of the Non-Cooperation Movement—following the Chauri Chaura incident in 1922, where a violent clash resulted in the deaths of several policemen—Surya Sen and his associates renewed their commitment to armed revolution. The group believed that a successful uprising required access to firearms and other weapons. To finance these efforts, they began planning a series of robberies as a means to raise the necessary funds.

Political dacoities

In August 1923, a dacoity was carried out at the residence of Seth Mahajan in the village of Paraikora, located under the jurisdiction of Anwara police station. The operation was led by Nirmal Sen and Ananta Singh. Other participants included Nogen Sen, Upen Bhattacharya, Sudhangshu Dasgupta, and Premananda Dutta. The group managed to obtain approximately ₹600–700 in cash and ornaments. At the time, the perpetrators remained unidentified by the police.

The next major operation took place on 14 December 1923. On that day, salaries for workers and staff of the East Bengal Railway workshop at Pahartali Thana were being transported from the Chittagong court treasury. The funds were carried in a horse-drawn cart, accompanied by the railway treasurer, several clerks, and armed police guards.

At approximately 10:00 a.m., the cart reached a secluded area known as "Tiger Pass", where it was ambushed by a group led by Ananta Singh. The assailants seized a bag containing ₹17,000 and fled the scene without being apprehended.

Nirmal Sen was reportedly meant to participate in the Tiger Pass operation but was unable to arrive on time due to unforeseen circumstances. According to some accounts, he expressed lasting regret over his absence from the mission.

Arrest under Bengal Ordinance act

The Bengal Criminal Law Amendment act, implemented under Robert Bulwer-Lytton, 1st Earl of Lytton, aimed to suppress revolutionary nationalism in Bengal. Expanding upon powers granted by Regulation III of 1818, the law permitted indefinite detention without trial. Charles Tegart, the Police Commissioner of Calcutta, was instrumental in enforcing the act and directed efforts primarily against groups such as Jugantar. The act led to widespread arrests of revolutionaries across undivided Bengal. Among those apprehended were Ambika Chakrabarty, Ananta Singh, and Ganesh Ghosh, while Surya Sen and Charu Bikash Dutta evaded capture by going underground.

Following instructions from Surya Sen, also known as "Masterda," Deben Dey and Nirmal Sen were dispatched to Burma (now Myanmar) to raise funds and procure arms. Deben Dey later moved to Singapore, while Sen remained in Rangoon, where he established a cloth business on Lewis Street. The business served as a front for covert revolutionary activities, including the smuggling of weapons into Chittagong. During this period, Manindralal Majumdar, Lokenath Bal, and Rajendra Dasgupta joined him in Burma.

In 1925, after learning of his father's death, Sen returned to India. He was arrested shortly thereafter along with Lokenath Bal and Rajendra Dasgupta. All three were released in 1928. Surya Sen and Anurup Sen were also arrested in 1926 under the same act and released in 1928. Anurup Sen, however, fell seriously ill while in custody and died later that year due to lack of proper medical care.

With Nogen Sen's withdrawal from revolutionary activities, the group’s leadership required restructuring. A new central committee was formed, appointing Surya Sen as president and Ambika Chakrabarty as vice-president. Nirmal Sen, Ganesh Ghosh, and Ananta Singh were inducted as key members of the committee.

In May 1929, a major political conference was held under the presidency of Subhas Chandra Bose. Shortly afterward, a secret meeting of the restructured central committee was convened, during which it was resolved that the Chittagong branch of the Indian Republican Army would launch an armed uprising on 18 April 1930. Nirmal Sen and Lokenath Bal were tasked with the critical objective of capturing the Auxiliary Force armoury.

From left: Nirmal Sen on his first arrest under Bengal Ordinance act; Nirmal Sen while being a student at Chittagong medical college.

The armoury raid and Jalalabad fight

On 19 December 1929, the Indian National Congress passed the historic Purna Swaraj (complete independence) resolution at its Lahore session. Shortly afterwards, nationalist leaders, including Subhas Chandra Bose who presided over the session, convened a secret meeting of the newly formed central committee of the Chittagong revolutionary group. During this meeting, it was decided that the Chittagong branch of the Indian Republican Army would initiate an armed rebellion against British colonial rule on 18 April 1930. Nirmal Sen and Lokenath Bal were assigned the strategic objective of capturing the Auxiliary Force armoury.

On the night of 18 April 1930, at 10 p.m., the armed uprising commenced. The revolutionary leaders executed their plans with precision and courage. Notably, the operation concluded without any casualties among the revolutionaries, indicating careful planning and effective coordination.

Four days later, on 22 April 1930, the revolutionaries engaged British forces in the Battle of Jalalabad. In a fierce encounter, the British troops were compelled to retreat. During the battle, several firearms malfunctioned. Demonstrating quick thinking and resourcefulness, Nirmal Sen used lubricating oil—previously seized during earlier raids—to restore the weapons to working order. This action proved crucial in maintaining the revolutionaries’ momentum and securing their tactical victory.

Aftermath

Following the Battle of Jalalabad, the group of 51 revolutionaries involved in the Chittagong Armoury Raid split into smaller factions to avoid arrest by British authorities. Of these, 23 fighters came under the leadership of Lokenath Bal, while the remaining 17 remained with Surya Sen and Nirmal Sen. One of the youngest revolutionaries, Subodh Roy (also known as Junku), who had been recruited by Nirmal Sen in 1927 at the age of eleven, guided Masterda’s group to his native village. The revolutionaries found temporary shelter and rest there before dispersing further to evade capture.

Nirmal Sen’s nephew, Srihari Sen, later recalled a brief visit from his uncle during the period when Nirmal was in hiding :

“One day, my uncle quietly returned home. Without saying much, he gathered every photograph of himself and began tearing them into tiny pieces. We were stunned. ‘Why are you destroying your own photos?’ we asked him. He looked up, calm but resolute, and said: ‘I know I won’t live much longer. But I don’t want the police to recognize this house because of my face. If they find out who I am, they’ll torture all of you. I can’t let that happen. And one more thing—I don’t want anyone sitting here crying over my picture after I’m gone. I want no trace of me left in this house."

Seeking shelters

Manindralal Majumdar, a prominent revolutionary and skilled sailor operating primarily in the Sripur and Haola areas, played a crucial role in Surya Sen’s movement. Not initially targeted by the police, Majumdar’s residence on the banks of the Karnaphuli River, surrounded by coconut and betel nut palms, served as a clandestine meeting place for Surya Sen, Nirmal Sen and other revolutionaries. The garden of this residence was occasionally used as a makeshift studio to photograph revolutionaries preparing for critical missions.

Majumdar’s nautical expertise was vital in assisting Surya Sen and Nirmal Sen to cross the Karnaphuli River under the cover of darkness during secret operations. He was also assigned to provide a sampan for an intended jailbreak, reflecting the trust and responsibility vested in him by the revolutionary network.

Another important sanctuary was the home of Bireswar Chakraborty in the village of Dhalghat near Chittagong. Despite its proximity to the Patiya Upazila military camp, this house functioned as a key refuge for fugitives, including Surya Sen and Nirmal Sen. The safety provided by this refuge was largely due to Sabitri Devi, the widowed wife of Bireswar Chakraborty, who lived there with her children, Snehalata and Ramkrishna. Surya Sen and Nirmal Sen often stayed on the upper floor of this two-story building, which served as a vital hideout during critical phases of the revolutionary struggle.

Among the trusted members of this network was Monoranjan Ray, also known as Kebla Da. Ray played a significant role in connecting prominent revolutionaries such as Pritilata Waddedar and Kalpana Datta with Surya Sen’s movement. He was actively involved in transporting explosives and participated in the Dynamite Conspiracy. Monoranjan Ray was arrested in November 1930.

Pritilata sought refuge at Sabitri Devi’s residence starting 11 June 1932. Prior to her arrival, other revolutionaries including Ramakrishna Biswas and Kalipada Chakrabarty had also used the house as a safe haven. Pritilata was a distinguished graduate of Bethune College, earning her B.A. degree in 1932. Known as “Rani” for her academic excellence, she balanced her revolutionary activities with her role as headmistress of Nandankanan,Chittagong girls’ school.

The Dhalghat Encounter

On the evening of 12 June 1932, around 9 p.m., Surya Sen, Nirmal Sen, and their comrades Apurba Sen (alias Bhola) and Pritilata Waddedar were nearly finished with dinner at the residence of Sabitri Devi. Snehalata, Sabitri Devi’s daughter, discreetly alerted them to the approach of a large group of unfamiliar men nearby—a task often entrusted to younger family members in revolutionary households due to their vigilance.

The two-storey mud house was soon surrounded by police forces led by Captain Cameron of the 2/8th Gurkhas and Inspector Manoranjan Bose. Suspecting revolutionaries were hiding on the upper floor, the officers ascended the external staircase. When the havildar led the way up, he was suddenly pushed through a narrow doorway and fell. At this moment, Nirmal Sen, armed with a Webley Revolver, confronted Captain Cameron at close range and fatally shot him.

The British forces then opened fire on the house, with the revolutionaries returning intermittent gunfire. Recognising the importance of Surya Sen’s leadership, Nirmal urged him, along with Apurba and Pritilata, to escape through the rear while he provided covering fire. Apurba Sen ran down the stairs but was confronted by an armed rifleman in the courtyard and was fatally shot while attempting to flee.

Meanwhile, Nirmal Sen attempted to escape through a window in the upper storey but was wounded by gunfire, forcing him to retreat back into the room for cover.

Later, Inspector Manoranjan Bose summoned reinforcements from the nearby Patiya Military Camp, returning with fifteen additional riflemen and a Lewis gun. A tighter perimeter was established, and concentrated fire was directed at the upper room where Nirmal was believed to be hiding. Despite occasional revolver shots fired from the window, the revolutionaries failed to hit any targets.

After the Lewis gun gunfire ceased, no further movement was detected inside the room. At dawn, Apurba Sen’s body was found in a hedge beside the house, with two revolvers—one in his hand and another tucked in his waistband. Nirmal Sen was discovered dead inside the upper room, having sustained multiple gunshot wounds.

Pritilata Waddedar , later reflected on her brief interactions with Nirmal Sen. In her writings, she noted:

“In my short interviews with Nirmalda, I recognised his noble and beautiful heart in which staunch revolutionary principles and strong religious temperament so nicely combined. I am fortunate that I got opportunities to come in touch with such a great soul that silently passed away from the world without giving the countrymen any opportunity to know how pure, how uncommon he was.”

Her words highlight the profound impression Nirmal Sen left on those who knew him. His death had a significant impact on Pritilata, shaping her resolve and influencing her subsequent actions in the revolutionary struggle. In her writings, she reflected on the loss of a courageous comrade :

“Nirmalda’s tragic end gave me a severe shock, and I became more desperate. The result of B.A. Examination was out by this time and I passed with Distinction. A few days after, I plunged myself heart and soul into the revolutionary preparations, leaving for good my beloved family.”

The bodies of the martyrs from the Dhalghat encounter, Nirmal Sen and Apurba Sen, were bound by their feet with a rope and dragged to the Dhalghat railway station. This act was carried out by British military forces as a demonstration of retribution, even extending their vengeance to the deceased revolutionaries. Their remains were subsequently transported to a concealed location in the hills of Pahartali Ward, where they were secretly doused with petrol and set on fire.

Following Nirmal Sen’s death, his elder brother, Jamini Ranjan Sen, was dismissed from his position at the A.B. Railway. The family also endured ongoing harassment from the police in the aftermath.

Following the encounter, Surya Sen and Pritilata Waddedar managed to evade capture by slipping through the surrounding bushes. They proceeded to the residence of fellow revolutionary Mani Dutta, who guided them through nearly four miles of difficult terrain—including fields, water bodies, and narrow paths—under the cover of darkness. Their destination was a safe house in Jeshtopura village, known by the code name ‘Kutir,’ which belonged to Kaviraj Ashwini. This episode underscored the constant peril faced by members of the revolutionary network in Chittagong.

By the following morning, senior British officials—including the District Magistrate, the Superintendent of Police, and Major Gordon, commander of the local military unit—arrived at the site of the incident. Subsequently, Savitri Devi and her daughter Snehalata were taken into custody and charged with harbouring revolutionaries, a serious offence under colonial law. The trial, overseen by Magistrate Nrisingh Mukherjee, named several others as co-accused, including Ramkrishna Chakraborty, Mahendra Lal Biswas, Dinesh Dasgupta, and Ajit Biswas.

Bibliography

• Hemendranath Dasgupta, Bharater Biplab Kahini, II & III, Calcutta, 1948;
• Ramesh Chandra Majumdar, History of the Freedom Movement in India, III, Calcutta 1963;
• Indian Republican Armir Chattagram Biplab Vol. 2 by Prasaddas Mukhopadhyay.
• Agnigarbha Chattagram by Ananta Singh
• Pritilata by Ghosh, Shankar